Java Programing laungage

Core Java Tutorial

Introduction of Core Java

How To Install JDk and Set of Path

Syntax of java Program

Difference between Java and C/C++

Advantage and Disadvantage of Java

What is Java

Why Java is not Pure Object Oriented Language

Java has Following Features/Characteristics

Limitation of Java Language and Java Internet

Common Misconception about Java

Simple Program of Java

Integrated Development Environment in java

Compile and Run Java Program

Applet and Comments in Java

Tokens in Java

Keywords in Java

Identifier and Variables in Java

Literals/Constants

Data Type in Java

Assignments and Initialization in Java

Operators in Java

Rule of Precedence in Java

Operator on Integer and Separators in Java Programming

Java Control Flow of Statements

If and If-else Selection Statement

Nested If-else and If-else-If Selection Statement

switch case and conditional operator Selection Statement

for and while Loop

do..while and for each Loop

break and labeled break statement

continue and labeled continue statement

return Statement and exit() Method

Escape Sequence for Special Characters and Unicode Code

Constants and Block or Scope

Statement in Java

Conversions between Numeric Types in Java

Import Statement in Java

User Input in Java using Scanner Class

User Input in Java using Console Class

Array in Java

One Dimensional Array

Two Dimensional Array

Two Dimensional Array Program

Command Line Argument in Java

String args Types in Java

Uneven/Jagged array in java

Math Class Function and Constant

Math Class all Function used in a program

Enumerated Types in Java

Object Oriented Programming v/s Procedural Programming

Object Oriented Programming Concepts in Java

Introduction to Class,Object and Method in Java

Class Declaration in Java

Class & Objects in java

Encapsulation in Java

Modifiers/Visibility for a Class or Interrface or member of a Class

Polymorphism in Java

Runtime polymorphism (dynamic binding or method overriding)

jdk1.5 interview questions answers
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What is difference between jdk1.4 and jdk1.5?

Following is added into jdk1.5 .which was not into jdk1.4:

  1. Java Language Features
  2. Generics
  3. Enhanced for Loop
  4. Autoboxing/Unboxing
  5. Typesafe Enums
  6. Varargs
  7. Static Import
  8. Metadata (Annotations)
  9. Virtual Machine
  10. Class Data Sharing
  11. Garbage Collector Ergonomics
  12. Server-Class Machine Detection
  13. Thread Priority Changes
  14. Fatal Error Handling
  15. High-Precision Timing Support

So many other new features has been added.

How Java 5.0 will help making Java an easier and more effective language to work with?

Bloch summarizes the answer to this question with two main points saying that Java 5.0 will help shifting the responsibility of writing the boilerplate code from the programmer to the compiler and he believes that the whole will be greater than the sum of its parts.

Generics, Autoboxing, Enhanced for-loop are the features which shift quite a lot coding responsibility from the programmer to the compiler. Humans are error prone and hence shifting the responsibility ultimately not only speeds up the development, but also makes the code more reliable and secure.

How does the "enhanced for-loop" help the developers?

This feature allows the programmers to forget about taking care of the iterators obtained from the Collections. The compiler automatically does that and it ensures that the iterators for each element in the Collection they have been obtained from.

Bloch says that having two extra keywords "foreach" and "in" could have made this even more readable and understandable, but that might have compromised with the compatbility with the earlier versions as the clients might have used these two words as identifiers in their programs.

What is Generic in Jdk1.5?

Generics:Provides compile-time (static) type safety for collections and eliminates the need for most typecasts (type conversion).

What is Meta Data in Jdk1.5?

Also called annotations, allows language constructs such as classes and methods to be tagged with additional data, which can then be processed by metadata- aware utilities

What is Autoboxing/Unboxing in Jdk1.5?

Automatic conversions between primitive types (such as int) and primitive wrapper classes (such as Integer).

What is Enumerations in Jdk1.5?

The enum keyword creates a typesafe, ordered list of values (such as Day.MONDAY, Day.TUESDAY, etc.). Previously this could only be achieved by non- typesafe constant integers or manually constructed classes (typesafe enum pattern).

What is the difference between “JDK” and “JRE”?

The “JDK” is the Java Development Kit.the JDK is bundle of software that you can use to develop Java based software.

The “JRE” is the Java Runtime Environment.the JRE is an implementation of the Java Virtual Machine which actually executes Java programs.

Each JDK contains one (or more) JRE’s along with the various development tools like the Java source compilers, bundling and deployment tools, debuggers, development libraries, etc.

JRE is a subset of JDK.

Two steps for a java program ie.,compile and interpret.

  1. JDK does compilation but JRE can’t.
  2. Both JRE and JDK does interpretaion.
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